Vehicle(s): 2006-08 Civic, 2006-08 Civic GX, and 2006-2011 Civic Hybrid

Details: If a Honda Civic, included within the year and model range listed above, comes in with diagnostic trouble code (DTC) P0606, Honda advises to first verify that the factory recommended spark plugs are installed. Aftermarket spark plugs may have built-in capacitors that can cause electrical interference, which will set DTC P0606. Also, the same DTC could set if the spark plugs are badly worn with a gap of 0.080” or more.

Suggested Repair: An easy way to diagnose this problem is to replace the aftermarket spark plugs first with the exact type that Honda recommends (find which spark plug Honda recommends quickly in the Maintenance section of ALLDATA Repair or Collision). Clear the DTC then complete a general drive cycle. If the DTC does not come back, the problem is solved. If the DTC does come back, continue with normal system troubleshooting.